In this study, molecular topology was used to develop several discriminant equations capable of classifying compounds according to their antibacterial activity.

Topological indices were used as structural descriptors and their relation to antibacterial activity was determined by applying linear discriminant analysis (LDA) on a group of quinolones and quinolone-like compounds.

Four extra equations were constructed, named DF3, DF4, DF5 and DF6 (DF1 and DF2 were built in a previous study), all with good statistical parameters such as Fisher-Snedecor F (> 25 in all cases), Wilk’s lambda (< 0.36 in all cases) and percentage of correct classification (> 80 % in all cases), which allows a reliable extrapolation prediction of antibacterial activity in any organic compound.

The results obtained clearly reveal the high efficiency of combining molecular topology with LDA for the prediction of antibacterial activity.